Your lungs aren't the only things that stand to benefit should California topple the U.S. Environmental Protection Agency in a battle over the regulation of tailpipe emissions.

Companies developing new emissions-reduction technologies, such as advanced catalytic converters, also stand to win.

While the national fuel-economy standard President Bush signed into law last month requires fuel-economy measures that will result in a full rejiggering of some cars, automakers could potentially meet California's standards simply by adding technologies that capture emissions, said Thilo Koslowski, a vice president and lead automotive analyst with Gartner (see Judge Upholds California Auto-Emission Law).

California Attorney General Jerry Brown on Wednesday filed another lawsuit against the EPA over the state's right to regulate tailpipe emissions.

"The EPA has done nothing at the national level to curb greenhouse gases and now it has wrongfully and illegally blocked California's landmark tailpipe emissions standards," Brown said in a written statement.

The lawsuit challenges the EPA's December decision denying a waiver that would have allowed California to enforce an emissions law requiring a 30 percent reduction in greenhouse-gas emissions from vehicles by 2016 (see EPA Rejects California Vehicle-Emission Standards).

Under the Federal Clean Air Act, California has the right to set its own vehicle-emissions standards as long as it obtains a waiver from the EPA. But the EPA claims the greenhouse gases are fundamentally global in nature, rather than being a local pollutant that states are allowed to regulate.

The Clean Air Act gives California the right to impose such standards if the state can prove "compelling and extraordinary conditions," Brown said. He pointed to evidence of global warming and its threat to California's Sierra mountain snow pack, which provides the state with one-third of its drinking water.

According to Brown, other states, including Massachusetts, Arizona, New Mexico, New York and Oregon, are joining California in the suit.

Meantime, the EPA said California's concerns already are being met by the federal Energy Independence and Security Act, signed into law last month, which boosts the fuel-economy standard by 40 percent to 35 miles per gallon (see President Signs Energy Bill). The EPA claims California's law would result in the equivalent of a fuel economy of only 33.5 miles per gallon.

"We now have a more beneficial national approach to a national problem which establishes an aggressive standard for all 50 states, as opposed to a lower standard in California and patchwork in other states," said Jonathan Shradar, an EPA spokesman.

But the California Air Resources Board disagrees, saying the state standard would yield a fuel economy of 44 miles per gallon in 2020. The board claims the state regulation would also more effectively reduce greenhouse gas emissions, as it includes things like air conditioning leaks, for example, that aren't addressed in the national standard.

Auto manufacturers also oppose the state law and have argued that the state's policy regulating emissions essentially sets fuel-economy standards, which can be set only by the federal government.

But Gartner's Koslowski said California's approach might be easier on carmakers than Washington's."In California, you can add things to the vehicle, but for [federal] standards, it seems like you have to do a little bit of reinventing," Koslowski said. "California raises the bar a little higher, but I think the [federal] standards are actually a bigger deal for car manufacturers."

Stanley Young, a spokesman for the Air Resources Board, said the board expects California's standard would add an extra $327 to vehicle price tags in 2009, when the standard would kick in, and would add more than $1,000 more by 2016.

That price hike includes the expected cost of new greenhouse-gas reduction technology, he said, which suggests the standard might make the Golden State an enticing market for companies with such technologies.